Capacity-modulated scroll compressor

ABSTRACT

A compressor may include a shell defining an internal volume containing compressed working fluid and first and second scrolls disposed within the internal volume. The first scroll may include a first spiral wrap. The second scroll may include a second spiral wrap, a suction inlet opening and a capacity-modulation aperture. The second spiral wrap may engage the first spiral wrap to define a pocket therebetween. The suction inlet opening may be sealed off from the internal volume. The capacity-modulation aperture may receive a valve member that is movable between a first position allowing leakage of fluid from the pocket to the suction inlet opening and a second position restricting leakage of fluid from the pocket.

FIELD

The present disclosure relates to a capacity-modulated scrollcompressor.

BACKGROUND

This section provides background information related to the presentdisclosure and is not necessarily prior art.

A climate-control system such as, for example, a heat-pump system, arefrigeration system, or an air conditioning system, may include a fluidcircuit having an outdoor heat exchanger, an indoor heat exchanger, anexpansion device disposed between the indoor and outdoor heatexchangers, and one or more compressors circulating a working fluid(e.g., refrigerant or carbon dioxide) between the indoor and outdoorheat exchangers. Efficient and reliable operation of the one or morecompressors is desirable to ensure that the climate-control system inwhich the one or more compressors are installed is capable ofeffectively and efficiently providing a cooling and/or heating effect ondemand.

SUMMARY

This section provides a general summary of the disclosure, and is not acomprehensive disclosure of its full scope or all of its features.

In one form, the present disclosure provides a compressor that mayinclude a shell, first and second scrolls and a valve member. The shellmay define an internal volume. The first scroll may be disposed withinthe internal volume and may include a first spiral wrap. The secondscroll may be disposed within the internal volume and may include asecond spiral wrap engaged with the first spiral wrap to form a pocketbetween the first and second spiral wraps. The second scroll may includea suction inlet opening, a discharge passage and a capacity-modulationaperture. The suction inlet opening may receive the fluid at a firstpressure and may be isolated from the internal volume. The dischargepassage may discharge the fluid to the internal volume at a secondpressure that is higher than the first pressure. The valve member may beat least partially disposed within the capacity-modulation aperture andmay be movable between a first position in which the valve memberrestricts fluid to flow around a tip of the first spiral wrap torestrict fluid communication between the suction inlet opening and thepocket and a second position in which the valve member allows fluid-flowaround the tip of the first spiral wrap to provide fluid communicationbetween the suction inlet opening and the pocket.

In some embodiments, the first scroll may be an orbiting scroll and thesecond scroll may be a non-orbiting scroll.

In some embodiments, an end of the valve member may be exposed to fluidwithin a fluid chamber. The fluid chamber may communicate with theinternal volume when the valve member is in a first position and maycommunicate with the suction inlet opening when the valve member is in asecond position.

In some embodiments, the compressor may include an actuation valvemovable between a first position allowing fluid communication betweenthe fluid chamber and the internal volume and restricting fluidcommunication between the fluid chamber and the suction inlet openingand a second position restricting fluid communication between the fluidchamber and the internal volume and allowing fluid communication betweenthe fluid chamber and the suction inlet opening.

In some embodiments, moving the actuation valve into the second positionallows the fluid chamber to fluidly communicate with the suction inletopening through an aperture formed in an end plate of the second scroll.

In some embodiments, the actuation valve may include apulse-width-modulated valve.

In some embodiments, the valve member may move between the first andsecond positions in response to response to a change in a pressuredifferential between the fluid chamber and the pocket.

In some embodiments, the valve member may include first and secondportions. The first portion may contact the first spiral wrap and may bedisposed between the second portion and the first spiral wrap. The firstportion may be formed from a material that allows the first portion towear faster than the second portion.

In another form, the present disclosure provides a compressor that mayinclude first and second scrolls, first and second valve members, amanifold and an actuation valve. The first scroll may include a firstend plate and a first spiral wrap extending from the first end plate.The second scroll may include a second end plate and a second spiralwrap extending from the first end plate and engaged with the firstspiral wrap. The second end plate may include a suction inlet openingand first and second capacity-modulation apertures extendingtherethrough. The first and second valve members may be at leastpartially disposed within the first and second capacity-modulationapertures, respectively, and movable therein to selectively providefirst and second leakage paths around a tip of the first spiral wrap.The manifold may include first and second chambers and a fluidpassageway fluidly connecting the first and second chambers. Themanifold may be positioned such that the first and second chambers arealigned with the first and second capacity-modulation apertures,respectively, such that portions of the first and second valve membersare exposed to the first and second chambers. The actuation valve may bein fluid communication with the fluid passageway and may be movablebetween a first position providing fluid communication between the fluidpassageway and the suction inlet opening and a second position providingfluid communication between the fluid passageway and a fluid sourcehaving a fluid pressure that is greater than a fluid pressure of thesuction inlet opening.

In some embodiments, the first and second capacity-modulation aperturesmay be positioned so that the first and second leakage paths fluidlyconnect the suction inlet opening with one or more pockets defined bythe first and second spiral wraps.

In some embodiments, the compressor may include first and second pocketsdefined by the first and second spiral wraps. The first and secondpockets may be sealed off from the suction inlet opening when the firstscroll is in a first orbital position. The first and secondcapacity-modulation apertures may be positioned so that when the firstscroll is in the first orbital position and the actuation valve is inthe first position, the first leakage path allows leakage from the firstpocket to the second pocket and the second leakage path allows leakagefrom the second pocket to the suction inlet opening.

In some embodiments, the second scroll may include a thirdcapacity-modulation apertures disposed between the first and secondcapacity-modulation apertures.

In some embodiments, the compressor may include a third valve member atleast partially disposed within the third aperture and movable thereinto selectively provide a third leakage path around a tip of the firstspiral wrap. The manifold may include a third chamber in communicationwith the fluid passageway and aligned with the third capacity-modulationaperture.

In some embodiments, the compressor may include a shell defining aninternal volume in which the first and second scrolls are disposed. Insome embodiments, the internal volume may be the fluid source.

In some embodiments, the suction inlet opening may be sealed off fromthe internal volume.

In some embodiments, the fluid passageway may be in communication withthe suction inlet opening through an aperture formed in the second endplate when the actuation valve is in the first position.

In some embodiments, the first scroll may be an orbiting scroll and thesecond scroll may be a non-orbiting scroll.

In some embodiments, the actuation valve may be a pulse-width-modulatedvalve.

In some embodiments, the first and second valve members may each includefirst and second portions. The first portion may contact the firstspiral wrap and may be disposed between the second portion and the firstspiral wrap. The first portion may be formed from a material that allowsthe first portion to wear faster than the second portion.

In another form, the present disclosure provides a high-side compressorthat may include a shell defining an internal volume containingcompressed working fluid and first and second scrolls disposed withinthe internal volume. The first scroll may include a first spiral wrap.The second scroll may include a second spiral wrap, a suction inletopening and a capacity-modulation aperture. The second spiral wrap mayengage the first spiral wrap to define a pocket therebetween. Thesuction inlet opening may be sealed off from the internal volume. Thecapacity-modulation aperture may receive a valve member that is movablebetween a first position allowing leakage of fluid from the pocket tothe suction inlet opening and a second position restricting leakage offluid from the pocket.

In some embodiments, the valve member allows leakage of fluid from saidpocket around a tip of said first spiral wrap to said suction inletopening.

In some embodiments, the second scroll may include anothercapacity-modulation aperture receiving another valve member that ismovable therein between a first position allowing leakage of fluid fromthe pocket to the suction inlet opening and a second positionrestricting leakage of fluid from the pocket.

In some embodiments, the high-side compressor may include another pocketdefined by the first and second spiral wraps. The pockets may be sealedoff from the suction inlet opening when the first scroll is in a firstorbital position. The capacity-modulation apertures may be positioned sothat when the first scroll is in the first orbital position and thevalve members are in the first positions, a leakage path is formed thatextends from one pocket, through the other pocket and into the suctioninlet opening.

In some embodiments, the first scroll may be an orbiting scroll and thesecond scroll may be a non-orbiting scroll.

In some embodiments, the high-side compressor may include another valvemember movable within another capacity-modulation aperture formed in thesecond scroll between a first position allowing leakage of fluid fromthe pocket to the suction inlet opening and a second positionrestricting leakage of fluid from the pocket.

In some embodiments, the valve members may be independently controlledand movable independently of each other between the first and secondpositions.

In some embodiments, the high-side compressor may include a manifold andan actuation valve operable in a first position to supply fluid to thevalve members at a first pressure to move the valve members to the firstposition and operable in a second position to supply fluid to the valvemembers at a second pressure that is higher than the first pressure tomove the valve members to the second position.

In some embodiments, an end plate of the second scroll may include afluid passageway in communication with the suction inlet opening. Theactuation valve may be in communication with a fluid passageway in thefirst position.

In some embodiments, the actuation valve may be in communication withthe internal volume in the second position.

In some embodiments, the valve members may allow leakage of fluid arounda tip of the first spiral wrap to the suction inlet opening.

In some embodiments, the actuation valve may be a pulse-width modulatedvalve.

In some embodiments, the valve member may include first and secondportions. The first portion may contact the first spiral wrap and may bedisposed between the second portion and the first spiral wrap. The firstportion may be formed from a material that allows the first portion towear faster than the second portion.

Further areas of applicability will become apparent from the descriptionprovided herein. The description and specific examples in this summaryare intended for purposes of illustration only and are not intended tolimit the scope of the present disclosure.

DRAWINGS

The drawings described herein are for illustrative purposes only ofselected embodiments and not all possible implementations, and are notintended to limit the scope of the present disclosure.

FIG. 1 is a cross-sectional view of a compressor according to theprinciples of the present disclosure;

FIG. 2 is a perspective view of a non-orbiting scroll andcapacity-modulation assembly of the compressor of FIG. 1;

FIG. 3 is an exploded perspective view of the non-orbiting scroll andcapacity-modulation assembly of FIG. 2;

FIG. 4 is a bottom view of the non-orbiting scroll;

FIG. 5 is a top view of the non-orbiting scroll and capacity-modulationassembly in a capacity-modulation mode;

FIG. 6 is a cross-sectional view of the non-orbiting scroll andcapacity-modulation assembly taken through line 6-6 of FIG. 5;

FIG. 7 is a cross-sectional view of the non-orbiting scroll andcapacity-modulation assembly taken through line 7-7 of FIG. 5;

FIG. 8 is a top view of the non-orbiting scroll and capacity-modulationassembly in a full-capacity mode;

FIG. 9 is a cross-sectional view of the non-orbiting scroll andcapacity-modulation assembly taken through line 9-9 of FIG. 8;

FIG. 10 is a partial cross-sectional view of the non-orbiting scroll,orbiting scroll, and capacity-modulation assembly in the full-capacitymode;

FIG. 11 is a partial cross-sectional view of the non-orbiting scroll,orbiting scroll, and capacity-modulation assembly in thecapacity-modulation mode;

FIG. 12 is a bottom view of the non-orbiting scroll including a firstorbital position of the orbiting scroll;

FIG. 13 is a bottom view of the non-orbiting scroll including a secondorbital position of the orbiting scroll;

FIG. 14 is a bottom view of the non-orbiting scroll including a thirdorbital position of the orbiting scroll;

FIG. 15 is a bottom view of the non-orbiting scroll including a fourthorbital position of the orbiting scroll;

FIG. 16 is a partial cross-sectional view of another non-orbitingscroll, orbiting scroll, and capacity-modulation assembly in afull-capacity mode according to the principles of the presentdisclosure;

FIG. 17 is a partial cross-sectional view of the non-orbiting scroll,orbiting scroll, and capacity-modulation assembly of FIG. 16 in thecapacity-modulation mode;

FIG. 18 is a top view of another non-orbiting scroll according to theprinciples of the present disclosure;

FIG. 19 is a partial cross-sectional view of the non-orbiting scroll ofFIG. 18, another orbiting scroll, and another capacity-modulationassembly in a full-capacity mode according to the principles of thepresent disclosure;

FIG. 20 is a partial cross-sectional view of the non-orbiting scroll,orbiting scroll, and capacity-modulation assembly of FIG. 19 in thecapacity-modulation mode;

FIG. 21 is a partial cross-sectional view of another non-orbitingscroll, orbiting scroll, and capacity-modulation assembly in afull-capacity mode according to the principles of the presentdisclosure;

FIG. 22 is a partial cross-sectional view of the non-orbiting scroll,orbiting scroll, and capacity-modulation assembly of FIG. 21 in thecapacity-modulation mode;

FIG. 23 is a partial cross-sectional view of another non-orbitingscroll, orbiting scroll, and capacity-modulation assembly in afull-capacity mode according to the principles of the presentdisclosure; and

FIG. 24 is a partial cross-sectional view of another non-orbitingscroll, orbiting scroll, and capacity-modulation assembly in afull-capacity mode according to the principles of the presentdisclosure.

Corresponding reference numerals indicate corresponding parts throughoutthe several views of the drawings.

DETAILED DESCRIPTION

Example embodiments will now be described more fully with reference tothe accompanying drawings.

Example embodiments are provided so that this disclosure will bethorough, and will fully convey the scope to those who are skilled inthe art. Numerous specific details are set forth such as examples ofspecific components, devices, and methods, to provide a thoroughunderstanding of embodiments of the present disclosure. It will beapparent to those skilled in the art that specific details need not beemployed, that example embodiments may be embodied in many differentforms and that neither should be construed to limit the scope of thedisclosure. In some example embodiments, well-known processes,well-known device structures, and well-known technologies are notdescribed in detail.

The terminology used herein is for the purpose of describing particularexample embodiments only and is not intended to be limiting. As usedherein, the singular forms “a,” “an,” and “the” may be intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. The terms “comprises,” “comprising,” “including,” and“having,” are inclusive and therefore specify the presence of statedfeatures, integers, steps, operations, elements, and/or components, butdo not preclude the presence or addition of one or more other features,integers, steps, operations, elements, components, and/or groupsthereof. The method steps, processes, and operations described hereinare not to be construed as necessarily requiring their performance inthe particular order discussed or illustrated, unless specificallyidentified as an order of performance. It is also to be understood thatadditional or alternative steps may be employed.

When an element or layer is referred to as being “on,” “engaged to,”“connected to,” or “coupled to” another element or layer, it may bedirectly on, engaged, connected or coupled to the other element orlayer, or intervening elements or layers may be present. In contrast,when an element is referred to as being “directly on,” “directly engagedto,” “directly connected to,” or “directly coupled to” another elementor layer, there may be no intervening elements or layers present. Otherwords used to describe the relationship between elements should beinterpreted in a like fashion (e.g., “between” versus “directlybetween,” “adjacent” versus “directly adjacent,” etc.). As used herein,the term “and/or” includes any and all combinations of one or more ofthe associated listed items.

Although the terms first, second, third, etc. may be used herein todescribe various elements, components, regions, layers and/or sections,these elements, components, regions, layers and/or sections should notbe limited by these terms. These terms may be only used to distinguishone element, component, region, layer or section from another region,layer or section. Terms such as “first,” “second,” and other numericalterms when used herein do not imply a sequence or order unless clearlyindicated by the context. Thus, a first element, component, region,layer or section discussed below could be termed a second element,component, region, layer or section without departing from the teachingsof the example embodiments.

Spatially relative terms, such as “inner,” “outer,” “beneath,” “below,”“lower,” “above,” “upper,” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. Spatiallyrelative terms may be intended to encompass different orientations ofthe device in use or operation in addition to the orientation depictedin the figures. For example, if the device in the figures is turnedover, elements described as “below” or “beneath” other elements orfeatures would then be oriented “above” the other elements or features.Thus, the example term “below” can encompass both an orientation ofabove and below. The device may be otherwise oriented (rotated 90degrees or at other orientations) and the spatially relative descriptorsused herein interpreted accordingly.

With reference to FIGS. 1-15, a high-side compressor 10 is provided thatmay include a shell assembly 12, a motor assembly 14, a compressionmechanism 16 and a capacity-modulation assembly 18. The shell assembly12 may include a cylindrical shell 20, an end cap 22 at an upper end ofthe shell 20 and a base 24 at a lower end of the shell 20. The shell 20,end cap 22 and base 24 may cooperate to define an internal volume 26containing high-pressure working fluid discharged by the compressionmechanism 16. The high-pressure working fluid may exit the internalvolume 26 through a discharge fitting 28 attached to the end cap 22 orthe shell 20, for example. A suction-inlet conduit 30 may be attached tothe end cap 22 or the shell 20, for example, and may extend through theinternal volume 26 and provide suction-pressure working fluid to thecompression mechanism 16. Suction-pressure fluid within thesuction-inlet conduit 30 may be fluidly isolated or sealed off from theinternal volume 26.

The motor assembly 14 may be disposed entirely within the internalvolume 26 and may include a stator 32, a rotor 34, and a driveshaft 36.The stator 32 may be press fit into the shell 20. The rotor 34 may bepress fit on the driveshaft 36 and may transmit rotational power to thedriveshaft 36. The driveshaft 36 may be rotatably supported by first andsecond bearing-housing assemblies 37, 39. The driveshaft 36 may includean eccentric crank pin 38 drivingly engaging the compression mechanism16.

The compression mechanism 16 may be disposed entirely within theinternal volume 26 and may include an orbiting scroll 40 and anon-orbiting scroll 42. The orbiting scroll 40 may include an end plate44 having a spiral wrap 46 extending therefrom. A cylindrical hub 48 mayproject downwardly from the end plate 44 and may include a drive bushing50 disposed therein. The crank pin 38 may drivingly engage the drivebushing 50. An Oldham coupling 52 may be engaged with the orbitingscroll 40 and the first bearing-housing assembly 37 or the non-orbitingscroll 42 to prevent relative rotation between the orbiting andnon-orbiting scrolls 40, 42.

The non-orbiting scroll 42 may include an end plate 54 and a spiral wrap56 projecting downwardly from the end plate 54. The spiral wrap 56 maymeshingly engage the spiral wrap 46 of the orbiting scroll 40, therebycreating a series of moving fluid pockets. The fluid pockets defined bythe spiral wraps 46, 56 may decrease in volume as they move from aradially outer position (at a low pressure) to a radially intermediateposition (at an intermediate pressure) to a radially inner position (ata high pressure) throughout a compression cycle of the compressionmechanism 16.

As shown in FIGS. 3 and 4, the end plate 54 may include a suction-inletopening 58, a discharge passage 60, first, second and thirdcapacity-modulation apertures 62, 64, 66, and a suction-communicationaperture 68. The suction-inlet opening 58 may sealingly engage thesuction-inlet conduit 30 so that suction-pressure working fluid from thesuction-inlet conduit 30 may be drawn into the compression mechanism 16(at the radially outer position) for subsequent compression between thespiral wraps 46, 56. The first, second and third capacity-modulationapertures 62, 64, 66 may be counterbored through-holes, each includingan annular shoulder 67 (FIG. 6). The suction-communication aperture 68may extend through the end plate 54 and may be in fluid communicationwith the suction-inlet opening 58 via a recess 70 (FIG. 4). Thedischarge passage 60 may be in communication with one of the fluidpockets at the radially inner position and allows compressed workingfluid to flow into the internal volume 26. A discharge valve (not shown)may provide selective fluid communication between the discharge passage60 and the internal volume 26.

The capacity-modulation assembly 18 may include a manifold 74, aplurality of capacity-modulation valve assemblies 76, and an actuationvalve 78. The manifold 74 can be fastened to the end plate 54 of thenon-orbiting scroll 42 by a plurality of fasteners 80 and/or by weldingand/or any other fastening means. In some embodiments, the manifold 74could be integrally formed with the non-orbiting scroll 42.

The manifold 74 may include first and second legs 81, 82 and first,second and third hubs 83, 84, 85. The first leg 81 may extend betweenthe first and second hubs 83, 84. The second leg 82 may extend betweenthe second and third hubs 84, 85. The first and second legs 81, 82 mayinclude first and second passageways 86, 87 (FIGS. 5 and 8),respectively, that are in fluid communication with each other. An endportion 88 of the first leg 81 may include an L-shaped passageway 89(FIG. 7) in communication with the suction-communication aperture 68 inthe non-orbiting scroll 42. In some embodiments, the manifold 74 couldinclude tubing to interconnect the hubs 83, 84, 85 rather than theintegrally formed legs 81, 82.

Each of the first, second and third hubs 83, 84, 85 may define a cavity90 (FIG. 6). Each cavity 90 may be in fluid communication with one orboth of the first and second passageways 86, 87 of the first and secondlegs 81, 82 through a corresponding port 91. The manifold 74 may bearranged relative to the end plate 54 such that the cavities of thefirst, second and third hubs 83, 84, 85 are substantially coaxiallyaligned with the first, second and third capacity-modulation apertures62, 64, 66, respectively. Gaskets 92 (FIG. 3) may be disposed betweenthe hubs 83, 84, 85 and the end plate 54 to provide a seal around thecapacity-modulation apertures 62, 64, 66 and the cavities 90.

Each of the capacity-modulation valve assemblies 76 may include a valvemember 94 and a spring 96. Each valve member 94 may include a headportion 98 and a stem portion 100. As shown in FIG. 6, the head portion98 of each valve member 94 may be movably received within the cavity 90of a corresponding one of the first, second and third hubs 83, 84, 85. Afluid chamber 79 (FIG. 7) may be defined by the cavity 90 and the valvemember 94 (e.g., between an end wall 97 of the cavity 90 and an end 99of the head portion 98). An O-ring 103 (FIG. 6) may engage a peripheryof the head portion 98 to provide a sealed relationship between the headportion 98 and an inner diametrical surface of the cavity 90. The stemportion 100 of each valve member 94 may extend from the correspondinghead portion 98 into a corresponding one of the first, second and thirdcapacity-modulation apertures 62, 64, 66. Each spring 96 may be disposedaround a corresponding stem portion 100 between the corresponding headportion 98 and corresponding shoulder 67 of the capacity-modulationapertures 62, 64, 66.

The valve members 94 are movable relative to the capacity-modulationapertures 62, 64, 66 and cavities 90 between a first position (FIG. 10)and a second position (FIG. 11). In the first position, the head portion98 may contact a top face 55 of the end plate 54, and a distal end 101of the stem portion 100 may sealingly engage (directly or indirectly viaa thin layer of lubricant) a tip 47 of the spiral wrap 46 of theorbiting scroll 40. In some embodiments, a minimal gap may be providedbetween the distal end 101 and the tip 47 in the first position. Thesprings 96 may bias the valve members 94 toward the second position. Inthe second position, the head portion 98 may be spaced apart from thetop face 55 and a leakage path may be formed between the distal end 101of the stem portion 100 and the tip 47 of the spiral wrap 46.

The actuation valve 78 (shown schematically in the figures) may beattached to the end portion 88 of the first leg 81 of the manifold 74and may include an outlet passage 102, a first inlet passage 104 (FIGS.5 and 7) and a second inlet passage 106 (FIG. 8). The outlet passage 102may be fluidly coupled with the first passageway 86 of the first leg 81.The first inlet passage 104 may be fluidly coupled to the L-shapedpassageway 89 in the end portion 88 of the first leg 81 (as shown inFIGS. 5 and 7). While FIG. 8 depicts the second inlet passage 106 influid communication with the internal volume 26, in some embodiments,the second inlet passage 106 may be in fluid communication with a pocketcontaining intermediate-pressure working fluid.

The actuation valve 78 may be actuated by a solenoid or any othersuitable device may move the actuation valve 78 between a firstconfiguration (FIG. 5) in which the outlet passage 102 is fluidlycoupled with the first inlet passage 104 and fluidly isolated from thesecond inlet passage 106 and a second configuration (FIG. 8) in whichthe outlet passage 102 is fluidly coupled with the second inlet passage106 and fluidly isolated from the first inlet passage 104. Accordingly,when the actuation valve 78 is in the first configuration, a fluidpathway is formed that extends between the fluid chambers 79 and thesuction-inlet opening 58 (i.e., through the suction-communicationaperture 68, the L-shaped passageway 89, the first inlet passage 104,the outlet passage 102 and the first and/or second passageways 86, 87)so that fluid within the fluid chambers 79 are at the same pressure asthe suction-inlet conduit 30 (i.e., suction pressure). When theactuation valve 78 is in the second configuration, a fluid pathway isformed that extends between the fluid chambers 79 and the internalvolume 26 (i.e., through the second inlet passage 106, the outletpassage 102 and the first and/or second passageways 86, 87) so thatfluid within the chambers 79 are at the same pressure as the internalvolume 26. The actuation valve 78 may be controlled by a control module(not shown) that moves the actuation valve 78 between the first andsecond configurations based on compressor operating parameters, systemoperating parameters and/or demand for heating or cooling, for example.

In some embodiments, the actuation valve 78 may be pulse-width-modulatedto achieve a desired operating capacity for the compressor 10. In someembodiments, the compressor 10 may include a plurality of actuationvalves 78, each of which may actuate a corresponding one of thecapacity-modulation valve assemblies 76. In this manner, each of thecapacity-modulation valve assemblies 76 may be independently actuated toprovide further control and levels of capacities at which the compressor10 may operate.

It will be appreciated that the number, shape and locations of thecapacity-modulation apertures 62, 64, 66 and capacity-modulation valveassemblies 76 can be varied from the configuration shown in the figures.In some configurations, the orbiting scroll 40 may includecapacity-modulation apertures 62, 64, 66 and capacity-modulation valveassemblies 76 (instead of or in addition to the capacity-modulationapertures 62, 64, 66 and capacity-modulation valve assemblies 76 of thenon-orbiting scroll 42) that open and close to selectively allow leakagearound a tip of the spiral wrap 56 of the non-orbiting scroll.

With continued reference to FIGS. 1-15, operation of the compressor 10will be described in detail. As described above, orbital motion of theorbiting scroll 40 relative to the non-orbiting scroll 42 may drawsuction-pressure working fluid into the compression mechanism 16 throughthe suction-inlet conduit 30 and suction-inlet opening 58. Thecompression mechanism 16 may compress the working fluid and dischargethe compressed working fluid to the internal volume 26. Thecapacity-modulation assembly 18 may be selectively operable in afull-capacity mode and in a reduced-capacity mode.

In the full capacity mode, the actuation valve 78 may be in the secondconfiguration (FIG. 8), which allows the fluid chambers 79 tocommunicate with the internal volume 26. When the fluid chambers 79 arein communication with the internal volume 26, relatively high pressurefluid in the chambers 79 forces the valve members 94 downward to thefirst position shown in FIG. 10 (i.e., pressure differentials arecreated between the fluid chambers 79 and one or more pockets 110 thatforces the valve members 94 downward to the first position). In thisposition, the valve members 94 restrict or prevent fluid from thepockets 110 (FIGS. 10 and 12) from leaking to a suction-pressure zone112 (i.e., a zone in communication with the suction-inlet opening 58 andsuction-inlet conduit 30).

In the reduced-capacity mode, the actuation valve 78 may be in the firstposition (FIG. 5), which allows the fluid chambers 79 to communicatewith the suction-inlet opening 58. When the fluid chambers 79 are incommunication with the suction-inlet opening 58, relatively low pressurefluid in the chambers 79 allows the springs 96 to force the valvemembers 94 upward to the second position shown in FIG. 11. In thisposition, leakage paths are formed between the tip 47 of the spiral wrap46 of the orbiting scroll 40 and the distal ends 101 of the valvemembers 94 that allows fluid from the pocket 110 to leak to thesuction-pressure zone 112.

In the reduced-capacity mode, the fluid in a given pocket 110 may onlybegin to be compressed once that pocket 110 has advanced far enoughradially inward (toward the discharge passage 60) that the pocket 110 issealed off from all of the capacity-modulation apertures 62, 64, 66.Because the start of compression is delayed until after the pocket 110is sealed off from the capacity-modulation apertures 62, 64, 66 (i.e.,at the position shown in FIG. 15), the working fluid in the pocket 110is subjected to less compression before the pocket 110 reaches thedischarge passage 60 and the fluid therein is discharged to the internalvolume 26.

By contrast, in the full-capacity mode, compression of the fluid withinthe pocket 110 begins earlier in the compression cycle (i.e., as soon asthe pocket 110 is sealed off from the suction-inlet open 58 andcommunication aperture 68 (at the position shown in FIG. 12). Becausethere is no leakage of fluid out of the pockets 110 in the full-capacitymode, the fluid within the pockets 110 undergoes additional compressionas is moves from the position shown in FIG. 12 to the position shown inFIG. 15 that the fluid is not subjected to in the reduced-capacity mode.Therefore, the fluid in the compression pockets 110 undergoes additionalcompression (i.e., the volume ratio is higher in the full-capacity modethan in the reduced-capacity mode) by the time it reaches the dischargepassage 60 and is discharged to the internal volume 26.

With reference to FIGS. 16 and 17, another capacity-modulation assembly218 and non-orbiting scroll 242 are provided. The capacity-modulationassembly 218 and non-orbiting scroll 242 can replace thecapacity-modulation assembly 18 and non-orbiting scroll 42 in thecompressor 10 described above. The structure and function of thecapacity-modulation assembly 218 and non-orbiting scroll 242 may besubstantially similar to that of the capacity-modulation assembly 18 andnon-orbiting scroll 42, apart from the exceptions described below andshown in the figures. Therefore, similar features will not be describedagain in detail.

As shown in FIGS. 16 and 17, capacity-modulation apertures 264 in thenon-orbiting scroll 242 may be formed so that a counterbore 267 has thesame diameter or a larger that the cavities 290 of manifold 274.Accordingly, top face 255 of end plate 254 of the non-orbiting scroll242 does not act as a hard stop that contacts head portions 298 of valvemembers 294 when the valve members 294 are in the first position (i.e.,the position corresponding to the full-capacity mode shown in FIG. 16).Rather, distal ends 301 of the stem portions 300 of the valve members294 may directly contact the tip 47 of the spiral wrap 46 of theorbiting scroll 40 in the full-capacity mode. A fluid chamber 279 may bedefined by the cavity 290 and the valve member 294 (e.g., between an endwall 297 of the cavity 290 and an end 299 of the head portion 298).

With reference to FIGS. 18-20, another capacity-modulation assembly 318and non-orbiting scroll 342 are provided. The capacity-modulationassembly 318 and non-orbiting scroll 342 can replace thecapacity-modulation assembly 18 and non-orbiting scroll 42 in thecompressor 10 described above. The structure and function of thecapacity-modulation assembly 318 and non-orbiting scroll 342 may besubstantially similar to that of the capacity-modulation assembly 18 andnon-orbiting scroll 42, apart from the exceptions described below andshown in the figures. Therefore, similar features will not be describedagain in detail.

The non-orbiting scroll 342 may include first, second and thirdcapacity-modulation apertures 362, 364, 366 that may each include afirst recess 368, a second recess 370 and a plurality of openings 372.The first and second recesses 368, 370 may be substantially concentricwith each other and may receive valve members 394 that are movabletherein between a first position corresponding to the full-capacity mode(FIG. 19) and a second position corresponding to the reduced-capacitymode (FIG. 20). The first recess 368 may include a larger diameter thanthe second recess 370 and may include an annular shoulder 374 engaging aspring 396. Stem portions 400 of the valve members 394 may seal againsta bottom face 376 of the second recess 370 in the first position torestrict or prevent fluid from pocket 410 flowing through one or more ofthe opening 372 into the second recess 370 and into a suction-pressurezone 412 through one or more other openings 372. In the second position,the stem portions 400 may be spaced apart from the bottom face 376 toallow fluid from pocket 410 to flow through one or more of the opening372 into the second recess 370 and into a suction-pressure zone 412through one or more other openings 372.

With reference to FIGS. 21 and 22, another capacity-modulation assembly418 is provided. The capacity-modulation assembly 418 can replace thecapacity-modulation assembly 18 in the compressor 10 described above.The structure and function of the capacity-modulation assembly 418 maybe substantially similar to that of the capacity-modulation assembly 18,apart from the exceptions described below and shown in the figures.Therefore, similar features will not be described again in detail.

The capacity-modulation assembly 418 may include a manifold 474, valvemembers 494, springs 496, and an actuation valve 478. The valve members494 and springs 496 may be similar or identical to the valve members 94and springs 96 described above. The manifold 474 may be similar to themanifold 74 described above, except that the manifold 474 may include anend portion 480 including a recess 482. The recess 482 may include anopen end 484, an outlet 486 and an inlet 488. The outlet 486 may befluidly coupled to fluid passageways 489 extending through the legs 490of the manifold 474. The inlet 488 may be fluidly coupled with thesuction-communication aperture 68 in the non-orbiting scroll 42.

The actuation valve 478 may include a valve body 491, a valve member 493and a solenoid coil 495. The valve body 491 may be a hollow, generallytubular member that may extend through an opening 498 in the shellassembly 12. The valve body 491 may include an internal cavity 500having a first inlet 502, a second inlet 504 and an outlet 506. Thefirst inlet 502 may provide fluid communication between the internalcavity 500 and the internal volume 26 of the compressor 10. The secondinlet 504 may be fluidly coupled with the inlet 488 of the recess 482 ofthe manifold 474. The outlet 506 may be fluidly coupled with the outlet486 of the recess 482. The valve body 491 may also include first andsecond valve seats 508, 510 disposed within the internal cavity 500. Thefirst valve seat 508 may surround a passage 512 that provides fluidcommunication between the first inlet 502 and the outlet 506. The secondvalve seat 510 may surround the second inlet 504.

The valve member 493 may be disposed within the internal cavity 500 andmay be movable therein between a first position corresponding to thefull-capacity mode (FIG. 21) and a second position corresponding to thereduced-capacity mode (FIG. 22). The valve member 493 may include a baseportion 514, a stem portion 516 and a head portion 518. The base portion514 may be disposed in the internal cavity 500 of the valve body 491adjacent a distal end 520 of the internal cavity 500. In this manner,the base portion 514 is at least partially surrounded by the solenoidcoil 495 so that energizing the solenoid coil with electrical currentmagnetically forces the valve member 493 upward toward the secondposition. A spring 522 may engage the base portion 514 and the distalend 520 of the internal cavity 500 and may bias the valve member 493toward the first position so that when the solenoid coil 495 is notenergized, the spring 522 forces the valve member 493 into the firstposition.

The stem portion 516 of the valve member 493 may extend between the baseportion 514 and the head portion 518 and through the passage 512 of theinternal cavity 500. The head portion 518 may include first and secondends 524, 526. When the valve member 493 is in the first position (FIG.21), the first end 524 may be spaced apart from the first valve seat 508and the second end 526 may sealingly engage the second valve seat 510.In this manner, when the valve member 493 is in the first position,fluid passageways 489 of the manifold 474 are sealed off from thesuction-communication aperture 68, but are allowed to communicate withthe internal volume 26 through the first inlet 502, the passage 512 andthe outlet 506. When the valve member 493 is in the second position(FIG. 22), the first end 524 may sealingly engage the first valve seat508 and the second end 526 may be spaced apart from the second valveseat 510. In this manner, when the valve member 493 is in the secondposition, fluid passageways 489 of the manifold 474 are sealed off fromthe internal volume 26, but are allowed to communicate with thesuction-inlet opening 58 through the suction-communication aperture 68,the inlet 488 of the recess 482, the second inlet 504 of the valve body491 and the outlet 506 of the valve body 491.

While the solenoid coil 495 and a portion of the valve body 491 aredescribed above and shown in FIGS. 21 and 22 as being disposed outsideof the shell assembly 12, it will be appreciated that the entireactuation valve 478 could be disposed within the shell assembly 12.However, the configuration depicted in FIGS. 21 and 22 may allow thesolenoid coil 495 to be more easily accessed by a user or servicetechnician in the event that the solenoid coil 495 needs to be replacedor serviced, for example. Furthermore, configurations in which thesolenoid coil 495 is disposed outside of the shell assembly 12 provide acooler operating environment for the solenoid coil 495, which mayimprove the longevity of the solenoid coil 495.

With reference to FIG. 23, another capacity-modulation assembly 618 isprovided. The capacity-modulation assembly 618 can replace thecapacity-modulation assembly 18 in the compressor 10 described above.The structure and function of the capacity-modulation assembly 618 maybe substantially similar to that of the capacity-modulation assembly 18,apart from the exceptions described below and shown in the figures.Therefore, similar features will not be described again in detail.

The capacity-modulation assembly 618 may include a manifold 674, aplurality of capacity-modulation valve assemblies 676, and an actuationvalve (not shown). The manifold 674 and actuation valve may be similaror identical to any of the manifolds 74, 274, 474 and actuation valves78, 478 described above. Each of the capacity-modulation valveassemblies 676 may include a valve member 694 and a spring 696. Thevalve member 694 may include a head portion 700 and a stem portion 702.In some embodiments, the head portion 700 and the stem portion 702 maybe initially formed as separate pieces and/or from different materials.For example, the stem portion 702 may be formed from a softer materialthat will wear relatively quickly in response to friction between adistal end 704 of the stem portion 702 and the tip 47 of the spiral wrap46 of the orbiting scroll 40 during operation of the compressor 10.Accordingly, the stem portion 702 may be manufactured to include anaxial length that causes a gap to exist between the top face 55 of theend plate 54 of the non-orbiting scroll 42 and a bottom face 706 of thehead portion 700 when the capacity-modulation assembly 618 is in thefull-capacity mode.

After assembly of the compressor 10, operating the compressor 10 willcause the tip 47 of the spiral wrap 46 to wear material off of thedistal end 704 of the stem portion 702 until the axial length of thestem portion 702 is reduced to an extent at which the bottom face 706 ofthe head portion 700 contacts the top face 55 of the end plate 54 whenthe capacity-modulation assembly 618 is in the full-capacity mode (asshown in FIG. 23). Once the stem portion 702 has worn down to thislength, minimal contact may exist between the stem portion 702 and thetip 47 of the spiral wrap 46 that will provide sufficient sealingtherebetween without unnecessary loading on the tip 47. This process ofwearing-in the valve member 694 may eliminate the need to tightlycontrol tolerances on the axial length of the valve member 694, whilestill providing optimal engagement between the valve member 694 and thetip 47.

With reference to FIG. 24, another capacity-modulation assembly 818 isprovided. The capacity-modulation assembly 818 can replace thecapacity-modulation assembly 18 in the compressor 10 described above.The structure and function of the capacity-modulation assembly 818 maybe substantially similar to that of the capacity-modulation assembly 18,apart from the exceptions described below and shown in the figures.Therefore, similar features will not be described again in detail.

The capacity-modulation assembly 818 may include a manifold 874, aplurality of capacity-modulation valve assemblies 876, and an actuationvalve (not shown). The manifold 874 and actuation valve may be similaror identical to any of the manifolds 74, 274, 474, 674 and actuationvalves 78, 478 described above. Each of the capacity-modulation valveassemblies 876 may include a valve member 894 and a spring 896. Thevalve member 894 may include a body 900 and a cap 902. The body 900 mayinclude a head portion 904 and a stem portion 906. The cap 902 may becup-shaped member having a generally U-shaped cross section. The stemportion 906 may be fixedly received within the cap 902.

In some embodiments, the body 900 and the cap 902 may be initiallyformed as separate pieces and/or from different materials. For example,the cap 902 may be formed from a softer material that will wearrelatively quickly in response to friction between the cap 902 and thetip 47 of the spiral wrap 46 of the orbiting scroll 40 during operationof the compressor 10. Accordingly, the cap 902 may be manufactured sothat an axial end 908 of the cap 902 includes an thickness that causes agap to exist between the top face 55 of the end plate 54 of thenon-orbiting scroll 42 and a bottom face 910 of the head portion 904when the capacity-modulation assembly 818 is in the full-capacity mode.

After assembly of the compressor 10, operating the compressor 10 willcause the tip 47 of the spiral wrap 46 to wear material off of the axialend 908 of the cap 902 until the overall axial length of the valvemember 894 is reduced to an extent at which the bottom face 910 of thehead portion 904 contacts the top face 55 of the end plate 54 when thecapacity-modulation assembly 818 is in the full-capacity mode (as shownin FIG. 24). Once the cap 902 has worn down to this thickness, minimalcontact may exist between the cap 902 and the tip 47 of the spiral wrap46 that will provide sufficient sealing therebetween without unnecessaryloading on the tip 47. This process of wearing-in the valve member 894may eliminate the need to tightly control tolerances on the axial lengthof the valve member 894, while still providing optimal engagementbetween the valve member 894 and the tip 47.

In some embodiments, the cap 902 could be a coating that is applied tothe bottom of the body 900 of the valve member 894. Such a coating couldbe applied to form the cup shape of the cap 902 shown in FIG. 24 or thecoating could be applied only to the axial end of the stem portion 906

In this application, the term “module” may be replaced with the term“circuit.” The term module may refer to, be part of, or include anApplication Specific Integrated Circuit (ASIC); a digital, analog, ormixed analog/digital discrete circuit; a digital, analog, or mixedanalog/digital integrated circuit; a combinational logic circuit; afield programmable gate array (FPGA); a processor (shared, dedicated, orgroup) that executes code; memory (shared, dedicated, or group) thatstores code executed by a processor; other suitable hardware componentsthat provide the described functionality; or a combination of some orall of the above, such as in a system-on-chip.

The foregoing description of the embodiments has been provided forpurposes of illustration and description. It is not intended to beexhaustive or to limit the disclosure. For example, the principles ofthe present disclosure are applicable to low-side compressors. Further,individual elements or features of a particular embodiment are generallynot limited to that particular embodiment, but, where applicable, areinterchangeable and can be used in a selected embodiment, even if notspecifically shown or described. The same may also be varied in manyways. Such variations are not to be regarded as a departure from thedisclosure, and all such modifications are intended to be includedwithin the scope of the disclosure.

What is claimed is:
 1. A compressor comprising: a shell defining aninternal volume; a first scroll disposed within said internal volume andincluding a first spiral wrap; a second scroll disposed within saidinternal volume and including a second spiral wrap engaged with saidfirst spiral wrap to form a pocket between said first and second spiralwraps, said second scroll including a suction inlet opening, a dischargepassage and a capacity-modulation aperture, said suction inlet openingreceiving said fluid at a first pressure and being isolated from saidinternal volume, said discharge passage discharging said fluid to saidinternal volume at a second pressure that is higher than said firstpressure; and a valve member at least partially disposed within saidcapacity-modulation aperture and movable between a first position inwhich said valve member restricts fluid to flow around a tip of saidfirst spiral wrap to restrict fluid communication between said suctioninlet opening and said pocket and a second position in which said valvemember allows fluid-flow around said tip of said first spiral wrap toprovide fluid communication between said suction inlet opening and saidpocket.
 2. The compressor of claim 1, wherein an end of said valvemember is exposed to fluid within a fluid chamber, said fluid chambercommunicating with said internal volume when said valve member is insaid first position and communicating with said suction inlet openingwhen said valve member is in said second position.
 3. The compressor ofclaim 2, further comprising an actuation valve movable between a firstposition allowing fluid communication between said fluid chamber andsaid internal volume and restricting fluid communication between saidfluid chamber and said suction inlet opening and a second positionrestricting fluid communication between said fluid chamber and saidinternal volume and allowing fluid communication between said fluidchamber and said suction inlet opening.
 4. The compressor of claim 3,wherein moving said actuation valve into said second position allowssaid fluid chamber to fluidly communicate with said suction inletopening through an aperture of an end plate of said second scroll. 5.The compressor of claim 2, wherein said valve member moves between saidfirst position and said second position responsive to a change in apressure differential between said fluid chamber and said pocket.
 6. Thecompressor of claim 1, wherein said valve member includes a firstportion and a second portion, said first portion contacting said firstspiral wrap and disposed between said second portion and said firstspiral wrap, said first portion being formed from a material that allowssaid first portion to wear faster than said second portion.
 7. Acompressor comprising: a first scroll including a first end plate and afirst spiral wrap extending from said first end plate; a second scrollincluding a second end plate and a second spiral wrap extending fromsaid first end plate and engaged with said first spiral wrap, saidsecond end plate including a suction inlet opening and first and secondcapacity-modulation apertures; first and second valve members at leastpartially disposed within said first and second capacity-modulationapertures, respectively, and movable to selectively provide first andsecond leakage paths around a tip of said first spiral wrap; a manifoldincluding first and second chambers and a fluid passageway fluidlyconnecting said first and second chambers, said first and secondchambers being aligned with said first and second capacity-modulationapertures, respectively, and portions of said first and second valvemembers are exposed to said first and second chambers; and an actuationvalve in fluid communication with said fluid passageway and movablebetween a first position providing fluid communication between saidfluid passageway and said suction inlet opening and a second positionproviding fluid communication between said fluid passageway and a fluidsource having a fluid pressure that is greater than a fluid pressure ofsaid suction inlet opening.
 8. The compressor of claim 7, wherein saidfirst and second capacity-modulation apertures are positioned so thatsaid first and second leakage paths fluidly connect said suction inletopening with one or more pockets defined by said first and second spiralwraps.
 9. The compressor of claim 7, further comprising first and secondpockets defined by said first and second spiral wraps, said first andsecond pockets being sealed off from said suction inlet opening whensaid first scroll is in a first orbital position, wherein said first andsecond capacity-modulation apertures are positioned so that when saidfirst scroll is in said first orbital position and said actuation valveis in said first position, said first leakage path allows leakage fromsaid first pocket to said second pocket and said second leakage pathallows leakage from said second pocket to said suction inlet opening.10. The compressor of claim 9, wherein said second scroll includes athird capacity-modulation aperture disposed between said first andsecond capacity-modulation apertures.
 11. The compressor of claim 10,further comprising a third valve member at least partially disposedwithin said third capacity-modulation aperture and movable therein toselectively provide a third leakage path around a tip of said firstspiral wrap, and wherein said manifold includes a third chamber incommunication with said fluid passageway and aligned with said thirdcapacity-modulation aperture.
 12. The compressor of claim 7, furthercomprising a shell defining an internal volume in which said first andsecond scrolls are disposed, and wherein said fluid source is saidinternal volume.
 13. The compressor of claim 7, wherein said fluidpassageway is in communication with said suction inlet opening throughan aperture formed in said second end plate when said actuation valve isin said first position.
 14. A high-side compressor including a shelldefining an internal volume containing compressed working fluid andfirst and second scrolls, said first scroll including a first spiralwrap, said second scroll including a second spiral wrap, a suction inletopening and a capacity-modulation aperture, said second spiral wrapmeshingly engaging said first spiral wrap to define a pockettherebetween, said suction inlet opening being sealed off from saidinternal volume, said capacity-modulation aperture receiving a valvemember that is movable therein between a first position allowing leakageof fluid from said pocket to said suction inlet opening and a secondposition restricting leakage of fluid from said pocket.
 15. Thehigh-side compressor of claim 14, wherein said valve member allowsleakage of fluid from said pocket around a tip of said first spiral wrapto said suction inlet opening.
 16. The high-side compressor of claim 14,further comprising another valve member movable within anothercapacity-modulation aperture formed in said second scroll between afirst position allowing leakage of fluid from said pocket to saidsuction inlet opening and a second position restricting leakage of fluidfrom said pocket.
 17. The high-side compressor of claim 16, wherein saidvalve members are independently controllable and independently movablebetween said first and second positions.
 18. The high-side compressor ofclaim 16, further comprising a manifold and an actuation valve operablein a first position to supply fluid to said valve members at a firstpressure to move the valve members to said first position and operablein a second position to supply fluid to said valve members at a secondpressure that is higher than said first pressure to move said valvemembers to said second position.
 19. The high-side compressor of claim18, wherein an end plate of said second scroll includes a fluidpassageway in communication with said suction inlet opening, and whereinsaid actuation valve is in communication with a fluid passageway in saidfirst position.
 20. The high-side compressor of claim 19, wherein saidactuation valve is in communication with said internal volume in saidsecond position.
 21. The high-side compressor of claim 20, wherein saidvalve members allow leakage of fluid around a tip of said first spiralwrap to said suction inlet opening.